Less than 1mW not properly reported.

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w1qg
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Last seen: 3 weeks 11 hours ago
Joined: 2012/12/31 - 21:06
Less than 1mW not properly reported.

Greetings,

Lately I have been experimenting with very low power TX settings.

Here is an excerpt from the results:
....
2019-09-06 16:34 W1QG 3.570046 -2 0 CM87xg 0.001 KPH CM88mc 123 319
2019-09-06 16:46 W1QG 3.570046 -8 0 CM87xg 0.001 KPH CM88mc 123 319
2019-09-06 16:58 W1QG 3.570046 -29 0 CM87xg 0.001 KPH CM88mc 123 319
2019-09-06 17:08 W1QG 3.570046 -26 0 CM87xg 0.001 KPH CM88mc 123 319
2019-09-06 17:18 W1QG 3.570046 -24 0 CM87xg 0.001 KPH CM88mc 123 319
2019-09-06 17:28 W1QG 3.570046 -4 0 CM87xg 0.001 KPH CM88mc 123 319
2019-09-06 17:38 W1QG 3.570046 -5 0 CM87xg 0.001 KPH CM88mc 123 319
.....

Before the 16:58 TX cycle, I changed my output power from 1mW down to 10uW (10e-6 W) and
changed the wsjtx application to be in sync with the new 10uW TX power.
The -20dB change is clear in the SNR data.
However, the reported power did not change from 1mW (0.001). After three cycles of 10uW
I changed back to 1mw and again the change in SNR is clear.

It appears that powers less than 1mw are either not transmitted correctly or not reported correctly.
Is this known?

Best regards,
Dick / w1qg